docs: def find_trivial_constructor(type_):
      """
      Returns reference to trivial constructor.
  
      Args:
          type_ (declarations.class_t): the class to be searched.
  
      Returns:
          declarations.constructor_t: the trivial constructor
  
      """
      assert isinstance(type_, class_declaration.class_t)
  
      trivial = type_.constructors(
          lambda x: is_trivial_constructor(x),
          recursive=False,
          allow_empty=True)
      if trivial:
          return trivial[0]
  
      return None